body {
    text-align: center;
    font-size: 25px;
}
.item {
    overflow: hidden;
}
aside {
    position: fixed;
    top: 0;
    left: 0;
    width: 0;
    height: 100%;
    display: flex;
    flex-flow: column nowrap;
    justify-content: space-between;
    align-items: stretch;
}
aside .item {
    width: 100%;
    height: 50%;
    flex: none;
}
.dirlist {
    padding: 20px;
    display: grid;
    grid-template-columns: 1fr;
    grid-gap: 30px 40px;
    justify-items: stretch;
    align-items: stretch;
    line-height: 50px;
}
.dirlist .item {
    min-width: 100%;
    max-width: 100%;
    height: 50px;
}
.imglist {
    padding: 10px;
}
.imglist img {
    display: block;
    height: 600px;
    margin: 10px auto;
}
@media (min-width: 400px) {
    aside {
        width: 50px;
    }
    .dirlist {
        margin-left: 50px;
        grid-template-columns: repeat(2, 1fr);
    }
    .imglist {
        margin-left: 50px;
    }
}
@media (min-width: 600px) {
    .dirlist {
        grid-template-columns: repeat(3, 1fr);
    }
}
@media (min-width: 800px) {
    .dirlist {
        grid-template-columns: repeat(4, 1fr);
    }
}
@media (min-width: 1000px) {
    .dirlist {
        grid-template-columns: repeat(5, 1fr);
    }
}
@media (min-width: 1200px) {
    .dirlist {
        grid-template-columns: repeat(6, 1fr);
    }
}
@media (min-width: 1400px) {
    .dirlist {
        grid-template-columns: repeat(7, 1fr);
    }
}
@media (min-width: 1600px) {
    .dirlist {
        grid-template-columns: repeat(8, 1fr);
    }
}
@media (min-width: 1800px) {
    .dirlist {
        grid-template-columns: repeat(9, 1fr);
    }
}
@media (min-width: 2000px) {
    .dirlist {
        grid-template-columns: repeat(10, 1fr);
    }
}
